Water level measuring system

Abstract

A water level measuring system according to an embodiment includes a support pipe installed in a water tank filled with a fluid to measure a water level and extending in a depth direction of the water tank, a support bar disposed at one side of the support pipe based on a central axis of the support pipe and extending in the depth direction of the water tank, a plurality of ultrasonic probes attached to the support bar and generating ultrasonic waves, and a water level calculator connected to the plurality of ultrasonic probes and calculating the water level of the water tank.

Description

TECHNICAL FIELD

[0001] The present application relates to a water level measuring system, and more particularly, to a water level measuring system using ultrasonic waves. BACKGROUND

[0002] Generally, the water level of cooling water filled inside a nuclear fuel reloading tank or a nuclear fuel storage tank of a nuclear power plant is monitored, and a safety response system and procedure are prepared accordingly. That is, in the nuclear fuel reloading tank or the nuclear fuel storage tank, a cooling process is performed on decay heat, and forced cooling is performed by a pump. At this time, in the case of the nuclear fuel storage tank, when the cooling function is lost or forced circulation is not performed, the fuel storage container boils, and then steam can be mixed. At this time, the water level must be monitored so that a replacement water source can be mobilized immediately, and even after the replacement water source is fed into the water, its situation must be monitored through continuous water level monitoring.

[0003] Generally, a water level is measured using a differential pressure type water level measuring method or an ultrasonic wave type water level measuring method. In the differential pressure type water level measuring method, when a bubble or steam is generated inside a water tank, it is difficult to measure the water level by differential pressure due to rapid fluctuation of fluid. The ultrasonic wave type water level measuring method measures a water level by calculating time between an ultrasonic wave emitted in a dense medium such as a liquid and a reflected ultrasonic wave or by using an interference fringe of an ultrasonic wave. The ultrasonic wave type water level measuring method is highly related to the presence of a reflected wave that is reflected after an ultrasonic wave is transmitted through a dense medium. When the situation is not normal, that is, when the cooling function of the nuclear fuel reloading tank or the nuclear fuel storage tank is lost, the cooling water boils, and a bubble or steam is rapidly generated, it is difficult to calculate a standardized reflected wave since the reflected wave disappears or is lost. Therefore, it is difficult to accurately measure the reflected wave, and there is also a limitation in measuring a water level. In particular, when a bubble is generated, it is difficult to accurately measure a water level since a waveform of an ultrasonic wave is not uniform.

[0004] In order to enhance these water level measuring methods, a thermal contact radar method, a thermal diffusion radar method, or a method of measuring a water level by imitating a shape of a radar are used, but in these methods, a complex module of a device for analysis and interpretation is combined with a device for analyzing radar type data that must be installed, so that the price and cost of the device increase. SUMMARY

[0005] TECHNICAL PROBLEM

[0006] The present embodiment relates to a water level measuring system capable of accurately measuring a water level even in an abnormal condition.

[0007] Technical Solution

[0008] A water level measuring system according to an embodiment includes a support pipe installed in a water tank filled with a fluid to measure a water level and extending in a depth direction of the water tank, a support bar disposed at one side of the support pipe based on a central axis of the support pipe and extending in the depth direction of the water tank, a plurality of ultrasonic probes attached to the support bar and generating ultrasonic waves, and a water level calculator connected to the plurality of ultrasonic probes and calculating a water level of the water tank.

[0009] The support bar can be in contact with an inner wall of the support pipe.

[0010] The ultrasonic probes can be installed at positions facing exposed inner walls of the support pipe.

[0011] The plurality of ultrasonic probes can propagate ultrasonic waves in a horizontal direction parallel to a surface of the fluid.

[0012] The water level calculator can calculate the water level of the water tank by using a number of ultrasonic probes among the plurality of ultrasonic probes that detect signals of reflected waves reflected from the support pipe.

[0013] When the number of ultrasonic probes is N, the length of the support bar is L, and the number of ultrasonic probes that detect signals of reflected waves is S, the water level in the water tank is calculated as (L / N)*S.

[0014] The plurality of ultrasonic probes can be disposed in the depth direction of the water tank.

[0015] The water level measuring system can further include a fixing member fixing the ultrasonic probes to the support bar.

[0016] The water tank can include a nuclear fuel reloading tank or a nuclear fuel storage tank of a nuclear power plant.

[0017] Advantageous Effects

[0018] According to an embodiment, since ultrasonic waves propagate in a space between the support bar and an inner wall of the support pipe, which space does not generate bubbles and steam, a water level can be accurately measured even in an abnormal condition in which bubbles or steam are generated inside the water tank.

[0019] In addition, since a water level of a fluid filled in a water tank can be measured using ultrasonic probes, which are low-cost devices, a water level can be quickly measured at a low cost compared to a method using expensive radar-type devices. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1is a diagram schematically showing a state in which the water level measuring system according to an embodiment is installed in a water tank.

[0021] Figure 2 is a partial perspective view of the water level measuring system according to an embodiment.

[0022] Figure 3 is a plan view of the water level measuring system according to an embodiment.

[0023] Figure 4 is a partial enlarged view of the water level measuring system according to an embodiment, and is a diagram showing a state in which ultrasonic waves are propagated above and below a water surface. DETAILED DESCRIPTION

[0024] Hereinafter, various embodiments of the present application will be described in detail so that those skilled in the art can easily carry out the present application with reference to the accompanying drawings. The present disclosure can be implemented in various different forms and is not limited to the embodiments described herein.

[0025] In order to clearly illustrate the present disclosure, parts irrelevant to the description are omitted, and the same or similar constituent elements are given the same reference numerals throughout the specification.

[0026] In addition, since the size and thickness of each configuration shown in the drawings are arbitrarily shown for better understanding and easy description, the present disclosure is not necessarily limited to the illustrated size and thickness.

[0027] Figure 1 is a diagram schematically showing a state in which the water level measuring system according to an embodiment is installed in a water tank. Figure 2 is a partial perspective view of the water level measuring system according to an embodiment. And Figure 3 is a plan view of the water level measuring system according to an embodiment.

[0028] As Figure 1 shown in FIG. 1. The water level measuring system according to an embodiment includes a support pipe 100, a support rod 200, a plurality of ultrasonic probes 300, a water level calculator 400, and a plurality of fixing members 500.

[0029] The support pipe 100 can be installed in the water tank 10 filled with the fluid 1 to measure the water level. The support pipe 100 can be elongated in the depth direction Y of the water tank 10 and can have a predetermined length L. The support pipe 100 can have a lower portion disposed below the water surface 1a of the fluid 1 filled in the water tank 10 and an upper portion disposed above the water surface 1a of the fluid 1. Accordingly, the fluid 1 can fill the inner space O of the support pipe 100. The support pipe 100 can be made of a material such as metal. The water tank 10 can include a nuclear fuel reloading tank or a nuclear fuel storage tank of a nuclear power plant. Accordingly, the present application can monitor the water level of the cooling water filled inside the water tank 10 of the nuclear power plant. However, the present application is not necessarily limited thereto and can be applied to various water tanks.

[0030] The support rod 200 can be disposed in the inner space O of the support pipe 100. The support rod 200 can be disposed at one side of the support pipe 100 based on the central axis C of the support pipe 100 and can extend in the depth direction Y. The length L of the support rod 200 can be the same as the length L of the support pipe 100. However, it is not necessarily limited thereto, and according to an embodiment, the length L of the support rod 200 can be different from the length L of the support pipe 100. The support rod 200 can be disposed at a side of the support pipe 100 which is in contact with the inner wall of the support pipe 100. Accordingly, the fluid 1 can be disposed in a narrow inner space O between the inner wall of the support pipe 100 and the support rod 200. Accordingly, even in the abnormal case where boiling occurs in the water tank 10 and gas bubbles or steam are generated, it is difficult for the gas bubbles or steam to exist in the fluid 1 disposed in the narrow space between the inner wall of the support pipe 100 and the support rod 200.

[0031] The plurality of ultrasonic probes 300 can be attached to the circumferential surface of the support rod 200 to generate ultrasonic waves L1 and L2 and can detect a reflected wave R. Further, the plurality of ultrasonic probes 300 can propagate ultrasonic waves in the horizontal direction X parallel to the surface 1a of the fluid 1. Accordingly, the ultrasonic waves generated by the plurality of ultrasonic probes 300 can be propagated to the inner wall of the support pipe 100. At this time, since it is difficult for gas bubbles and steam to exist on the path of the ultrasonic waves, the water level can be accurately measured.

[0032] The plurality of ultrasonic probes 300 can be spaced apart at a predetermined gap in the depth direction Y of the water tank 10.

[0033] The ultrasonic probe 300 can be installed on the circumferential surface of the support rod 200 at a position facing the exposed inner wall of the support pipe 100. Accordingly, ultrasonic waves can be generated in one direction from the support rod 200.

[0034] At this time, among the side walls filled with the support bars 200, the side walls to which the plurality of ultrasonic probes 300 are attached can not be in direct contact with the inner walls of the support pipes 100 facing each other, and can have a structure separated from each other. Accordingly, vibrations of the ultrasonic waves generated from the plurality of ultrasonic probes 300 attached to the support bars 200 can not directly affect the support pipes 100 spaced apart from the support bars 200, thereby eliminating interference of the ultrasonic waves, thereby more accurately measuring the water level.

[0035] That is, since the ultrasonic probes 300 are attached to the fixed support bars 200 filled inside to transmit the ultrasonic waves to the support pipes 100 not in direct contact with the ultrasonic probes 300, the ultrasonic waves between the ultrasonic probes 300 do not interfere with each other, thereby not generating an interference signal or a noise signal. Accordingly, since a complex additional device, for example, an arithmetic processing device, for processing the interference signal or the noise signal is not required, and each of the ultrasonic probes 300 independently measures the water level, a simple structure can be achieved, and manufacturing costs can be minimized.

[0036] Figure 4 is a partial enlarged view of the water level measuring system according to an embodiment, and is a view showing a state in which the ultrasonic waves are propagated above and below the water surface.

[0037] As shown in FIG. 1, Figure 4 Since the ultrasonic wave L1 generated by the ultrasonic probe 300 disposed below the water surface 1a is propagated inside the fluid 1, a reflected wave can be generated on the inner wall of the support pipe 100, and since the reflected wave R is again propagated to the ultrasonic probe 300, the ultrasonic probe 300 can detect the reflected wave.

[0038] In addition, since the ultrasonic wave L2 generated by the ultrasonic probe 300 disposed above the water surface 1a is not propagated inside the fluid 1, the ultrasonic wave L2 is dissipated or dispersed on the inner wall of the support pipe 100, so that the ultrasonic probe 300 cannot detect the reflected wave R.

[0039] The water level calculator 400 can be connected to the plurality of ultrasonic probes 300 to calculate the water level of the water tank 10. The water level calculator 400 can calculate the water level of the water tank 10 by summing the number of ultrasonic probes 300 in which the signal of the reflected wave R reflected from the support pipe 100 is detected among the plurality of ultrasonic probes 300.

[0040] That is, when the number of the plurality of ultrasonic probes 300 is N, the length of the support bar 200 (or the support pipe 100) is L, and the number of the ultrasonic probes 300 in which the signal of the reflected wave R is detected is S, the water level P of the water tank 10 can be expressed by Equation 1 below.

[0041] [Equation 1]

[0042] P = (L / N) * S

[0043] At this time, each of the ultrasonic probes 300 can be used as a channel for measuring the water level. That is, when the water level is measured with 100 channels in the water tank 10 filled with the fluid 1 having a water level of 6 m, 100 ultrasonic probes can be installed on the support bar 200 having a length of 6 m, and one ultrasonic probe 300 can be provided every 6 cm.

[0044] In addition, when the water level is measured with 150 channels in the water tank 10 having a water level of 4 m, 150 ultrasonic probes can be installed on the support bar 200 having a length of 4 m, and one ultrasonic probe 300 can be provided every 2.67 cm. At this time, when the number of channels through which the signal of the reflected wave R is detected is 123 channels, the number S of ultrasonic probes 300 that detect the signal of the reflected wave R becomes 123. Therefore, since the total number N of ultrasonic probes 300 is 150 and the length L of the support bar 200 is 400 cm, the water level P of the water tank 10 can be calculated as (400 cm / 150) * 123 = 328.41 cm.

[0045] In addition, by increasing the number of channels, i.e., the number of ultrasonic probes 300, the water level of the water tank 10 can be more accurately measured.

[0046] As described above, in the water level measuring system according to the embodiment of the present application, the ultrasonic waves propagate in the space between the support bar 200 and the inner wall of the support pipe 100 in which no bubbles and steam are generated, so that the water level of the fluid 1 filled inside the water tank 10 can be more accurately measured.

[0047] In addition, since the water level of the fluid 1 filled in the water tank 10 can be measured using the ultrasonic probe 300, which is a low-cost device, the water level can be quickly measured at a low cost compared to a method using an expensive radar-type device.

[0048] The plurality of fixing members 500 can fix the plurality of ultrasonic probes 300 to the support bar 200. The fixing member 500 can include a first fixing member 510 and a second fixing member 520 installed to be in contact with the upper surface and the lower surface of the ultrasonic probe 300, respectively. Since the shaking of the ultrasonic probe 300 can be prevented by using the first fixing member 510 and the second fixing member 520, the water level can be more accurately measured by the ultrasonic probe 300.

[0049] Those skilled in the art will readily understand. Although the present disclosure has been described by way of preferred embodiments as set forth above, the present application is not limited thereto and various modifications and changes can be made without departing from the scope of the claims set forth below.

Claims

1. A water level measurement system, comprising: A support tube is installed in a fluid-filled water tank to measure the water level and extends in the depth direction of the water tank; A support rod, which is disposed on one side of the support tube based on the central axis of the support tube and extends in the depth direction of the water tank; Multiple ultrasonic probes are attached to the sidewall of the support rod and generate ultrasonic waves; and A water level calculator, connected to the plurality of ultrasonic probes, calculates the water level in the water tank. The plurality of ultrasonic probes propagate ultrasonic waves in a horizontal direction parallel to the surface of the fluid. The ultrasonic waves propagate between the support rod and the inner wall of the support tube and are reflected on the inner wall of the support tube. The side wall of the support rod to which the plurality of ultrasonic probes are attached does not directly contact the inner wall of the support tube.

2. The water level measurement system according to claim 1, wherein, The support rod is in contact with the inner wall of the support tube.

3. The water level measurement system according to claim 1, wherein, The ultrasonic probe is installed at a position facing the exposed inner wall of the support tube.

4. The water level measurement system according to claim 1, wherein, The water level calculator calculates the water level of the tank by using several ultrasonic probes that detect signals of reflected waves reflected from the support pipe.

5. The water level measurement system according to claim 4, wherein, When the number of ultrasonic probes is N, the length of the support rod is L, and the number of ultrasonic probes that detect the reflected wave signal is S, the water level of the water tank is calculated as (L / N)*S.

6. The water level measurement system according to claim 1, wherein, The plurality of ultrasonic probes are arranged along the depth direction of the water tank.

7. The water level measurement system according to claim 1 further includes a fixing member for fixing the ultrasonic probe to the support rod.

8. The water level measurement system according to claim 1, wherein, The tank includes a nuclear fuel refill tank or a nuclear fuel storage tank for a nuclear power plant.

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